Heat pump system control method for vehicle

ABSTRACT

A control method of a heat pump system for a vehicle may include a first cooling apparatus having a first radiator, a first water pump, an electrical component, a valve, and a branch line, which are connected by a first coolant line and circulate a first coolant by the first water pump to the electrical component; a second cooling apparatus including a second radiator and a second water pump connected by a second coolant line; and an air conditioning apparatus including a compressor, a heater, an expansion valve, and a heat exchanger which are connected by a refrigerant line circulated with a refrigerant.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No.10-2019-0091586 filed on Jul. 29, 2019, the entire contents of which isincorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a method for controlling a heat pumpsystem for a vehicle, and more particularly, to a method for controllinga heat pump system for a vehicle in which heat from an external heatsource is selectively recovered to be used in a heating mode whilerecovering thermal energy generated from an electrical component in anelectric vehicle.

Description of Related Art

A vehicle includes an air conditioning system as an air conditioner toheat or cool an interior of a vehicle.

The air conditioning system, which is to maintain the interior of thevehicle at an appropriate temperature regardless of a change in anexternal temperature to maintain a comfortable internal environment, isconfigured to heat or cool the interior of the vehicle through heatexchange by an evaporator in a process in which a refrigerant dischargedby driving of a compressor is circulated to the compressor through acondenser, a receiver drier, an expansion valve, and the evaporator.

That is, the air conditioning system lowers a temperature and a humidityof the interior by condensing a high-temperature high-pressure gas-phaserefrigerant compressed from the compressor by the condenser, passing therefrigerant through the receiver drier and the expansion valve, and thenevaporating the refrigerant in the evaporator in a cooling mode insummer.

Recently, as interest in energy efficiency and an environmentalcontamination problem is increased day by day, there is a demand fordeveloping an environmentally friendly vehicle which is configured forsubstantially replacing an internal combustion engine vehicle, and theenvironmentally friendly vehicle is commonly divided into an electricvehicle which is driven by use of a fuel cell or electricity as a powersource, and a hybrid vehicle which is driven by use of an engine and anelectric battery.

Here, the air conditioning system applied to the electric vehicle has acharacteristic of lowering the temperature and humidity of the interiorby condensing a high-temperature high-pressure gas-phase refrigerantcompressed from the compressor by the condenser, passing the refrigerantthrough the receiver drier and the expansion valve, and then evaporatingthe refrigerant in the evaporator in a cooling mode in summer, which isthe same as a general principle, but using a gaseous coolant of a hightemperature and high pressure as a heater medium in a heating mode inwinter.

However, the air conditioner system applied to the conventional electricvehicle as described above may increase the temperature of the air blowninto the vehicle interior by use of an electric heater provided in aheating, ventilation, and air conditioning (HVAC) module during theheating mode operation of the winter user. Accordingly, there is aproblem that the charge amount of the battery is reduced because theelectric heater supplied with a power source from the battery isexcessively used.

Furthermore, it is difficult to efficiently manage the battery, whichshortens the entire travel distance of the vehicle, deteriorating thecommerciality of the electric vehicle.

The information included in this Background of the present inventionsection is only for enhancement of understanding of the generalbackground of the present invention and may not be taken as anacknowledgement or any form of suggestion that this information formsthe prior art already known to a person skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing acontrol method of a heat pump system for minimizing a usage amount of anelectric heater by recovering thermal energy generated from anelectrical component when running in an electric vehicle and selectivelyrecovering heat of an external heat source when the heat source isinsufficient to be used in a heating mode of the vehicle.

The control method of the heat pump system for the vehicle according toan exemplary embodiment of the present invention to be used for heatingthe vehicle by selectively recovering thermal energy generated from theelectrical component and an external heat source when the vehicle isrunning, in a heat pump system including: a first cooling apparatusincluding a first radiator, a first water pump, an electrical component,a valve, and a branch line, which are connected by a first coolant lineand circulate a first coolant by the first water pump to the electricalcomponent; a second cooling apparatus including a second radiator and asecond water pump connected by a second coolant line; and an airconditioning apparatus including a compressor, a heater, an expansionvalve, and a heat exchanger which are connected by a refrigerant linecirculated with a refrigerant, and the heat exchanger is connected tothe first and second coolant lines respectively, and is controlled by acontroller, includes: (A) a process of performing heating of a vehicleinterior when the vehicle is running and operating the first coolingapparatus; (B) a process of detecting a temperature of a first coolantcirculated in the first cooling apparatus and a temperature of a secondcoolant in the second cooling apparatus and determining whether adifference value of the first coolant temperature and the second coolanttemperature is higher than a predetermined temperature; and (C) aprocess of controlling operation of the second water pump and finishingthe control by comparing the difference value of the temperature of thefirst coolant and the temperature of the second coolant with thepredetermined temperature through the process (B).

The process (A) may include: starting, by the controller, the heating ofthe vehicle according to an operation or setting of a user duringdriving of the vehicle by the controller; operating the compressor ofthe air conditioning apparatus by the controller; and controlling thevalve by the controller to open the branch line and to operate the firstwater pump.

If a heating mode of the vehicle is performed, in the state that thefirst coolant line connected to the branch line and the electricalcomponent are connected to each other, the valve may close the firstcoolant line connected to the first radiator by a control signal of thecontroller to stop an inflow of the coolant to the first radiator.

The process (B) may include: detecting a temperature of the first andsecond coolants by the controller through an output signal output fromthe first and second coolant temperature sensors; and determiningwhether a difference value of the temperature of the first coolant andthe temperature of the second coolant is higher than a predeterminedtemperature.

The first coolant temperature sensor may detect the temperature of thefirst coolant circulated in the first cooling apparatus, and the secondcoolant temperature sensor may detect the temperature of the secondcoolant circulated in the second cooling apparatus.

In the step of determining whether the difference of the first coolanttemperature and the second coolant temperature is higher than thepredetermined temperature, if the condition is satisfied, the process(C) may include maintaining a state in which an operation of the secondwater pump is interrupted or the operation of the second water pump isstopped or finishing the control.

In the step of determining whether the difference of the first coolanttemperature and the second coolant temperature is higher than thepredetermined temperature, if the condition is not satisfied, theprocess (C) may include operating the second water pump.

In the process (C), after operating the second water pump, the controlmethod may further include operating a cooling fan mounted at the rearof the first radiator or opening an active air flap provided in thevehicle at the front of the second radiator, and returning the controlmethod to the process (B).

The heat exchanger recovers the thermal energy from the first and secondcoolants inflowed through the first and second coolant lines in theheating mode of the vehicle, increasing the temperature of the coolantby use of the recovered heat energy.

As above-described, according to the control method of the heat pumpsystem for the vehicle according to an exemplary embodiment of thepresent invention, when driving the electric vehicle, the thermal energygenerated from the electrical component is recovered, and when the heatsource is insufficient, the heat from the external heat source isselectively recovered to be used to the heating mode of the vehicle,minimizing of the usage amount of the electric heater.

Furthermore, the present invention prevents excessive power consumptionof the electric heater, increasing the overall travel distance of thevehicle through efficient management of the battery, and also reducesthe battery charging cost by preventing unnecessary power consumption.

Furthermore, the present invention improves overall marketability byincreasing the travel distance of the vehicle and reducing the batterycharging cost.

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description, which together serve to explaincertain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a heat pump system to which a controlmethod of a heat pump system for a vehicle according to an exemplaryembodiment of the present invention is applied.

FIG. 2 is a control flowchart to explain a control method of a heat pumpsystem for a vehicle according to an exemplary embodiment of the presentinvention is applied.

It may be understood that the appended drawings are not necessarily toscale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the present invention.The specific design features of the present invention as includedherein, including, for example, specific dimensions, orientations,locations, and shapes will be determined in part by the particularlyintended application and use environment.

In the figures, reference numbers refer to the same or equivalentportions of the present invention throughout the several figures of thedrawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the presentinvention(s) will be described in conjunction with exemplary embodimentsof the present invention, it will be understood that the presentdescription is not intended to limit the present invention(s) to thoseexemplary embodiments. On the other hand, the present invention(s)is/are intended to cover not only the exemplary embodiments of thepresent invention, but also various alternatives, modifications,equivalents and other embodiments, which may be included within thespirit and scope of the present invention as defined by the appendedclaims.

An exemplary embodiment of the present invention will hereinafter bedescribed in detail with reference to the accompanying drawings.

Exemplary embodiments described in the exemplary embodiment andconfigurations shown in the drawings are just the most preferableexemplary embodiments of the present invention, but do not limit thespirit and scope of the present invention. Therefore, it should beunderstood that there may be various equivalents and modificationscapable of replacing them at the time of filing of the presentapplication.

To clarify the present invention, parts that are not connected with thedescription will be omitted, and the same elements or equivalents arereferred to by the same reference numerals throughout the specification.

The size and thickness of each element are arbitrarily shown in thedrawings, but the present invention is not necessarily limited thereto,and in the drawings, the thickness of layers, films, panels, regions,etc., are exaggerated for clarity.

Throughout this specification and the claims which follow, unlessexplicitly described to the contrary, the word “comprise” or variationssuch as “comprises” or “comprising” will be understood to imply theinclusion of stated elements but not the exclusion of any otherelements.

Furthermore, the terms, “ . . . unit”, “ . . . mechanism”, “ . . .portion”, “ . . . member”, etc. used herein mean a unit of inclusivecomponents performing at least one or more functions or operations.

FIG. 1 is a block diagram of a heat pump system to which a controlmethod of a heat pump system for a vehicle according to an exemplaryembodiment of the present invention is applied, and FIG. 2 is a controlflowchart to explain a control method of a heat pump system for avehicle according to an exemplary embodiment of the present invention.

Referring to FIG. 1, a control method of a heat pump system for avehicle according to an exemplary embodiment of the present invention iscontrolled by a controller 50, and is applied to a heat pump systemincluding an air conditioning apparatus 40 to which first and secondcooling apparatuses 10 and 20 are interconnected in an electric vehicle.

Here, the controller 50 may be electrically connected to first andsecond coolant temperature sensors 17 and 27, respectively, to confirm atemperature of a first coolant in the first cooling apparatus 10 and atemperature of a second coolant in the second cooling apparatus 20.

That is, the first coolant temperature sensor 17 may detect thetemperature of the first coolant circulated in the first coolingapparatus 10 and the second coolant temperature sensor 27 may detect thetemperature of the second coolant circulated in the second coolingapparatus 20 to be output to the controller 50.

In the exemplary embodiment of the present invention, the coolingapparatus 10 includes a first water pump 14 circulating the coolant toan electrical component 15 mutually connected by a first coolant line11, a first radiator 12 and a cooling fan 13 mounted at a front of thevehicle to cool the first coolant through heat exchange with externalair, a valve 16, and a branch line 18.

Here, the electrical component 15 may include an electric power controlunit (EPCU) and an on-board charger (OBC).

Also, one end portion of the branch line 18 is connected to the valve 16mounted at the first coolant line 11 between the first radiator 12 andthe first water pump 14, and the other end portion thereof is connectedto the first coolant line 11 between the first radiator 12 and theelectrical component 15.

Accordingly, when the first branch line 18 is open through operation ofthe valve 16 in the heating mode of the vehicle, the first branch line18 again circulates the first coolant passing through the electricalcomponent 15 to the electrical component 15 without passing through thefirst radiator 12, raising the temperature of the first coolant.

In the instant case, if the heating mode of the vehicle is performed, inthe state that the first coolant line 11 connected to the branch line 18and the electrical component 15 are connected to each other, the valve16 may close the first coolant line 11 connected to the first radiator12 by the control signal of the controller 50 to stop the inflow of thecoolant to the first radiator 12.

In the exemplary embodiment of the present invention, the second coolingapparatus 20 includes a second radiator 22 and a second water pump 24which are connected by a second coolant line 21. The second radiator 22may be mounted at the front of the first radiator 12.

Also, the air conditioning apparatus 40 may include a compressor 43, aheater 45, an expansion valve 47, and a heat exchanger 49 that areconnected by a refrigerant line 41 to which the refrigerant iscirculated.

First, the compressor 43 compresses the refrigerant of the gas stateinflowed through the refrigerant line 41 with high temperature/highpressure.

The heater 45 is an internal condenser provided inside thenon-illustrated HVAC module, and is connected to the compressor 43through the refrigerant line 41, condensing the refrigerant supplied bythe compressor 43 through heat exchange with external air.

The heater 45 may heat the interior of the vehicle by inflowing theoutside air having the elevated temperature while being heat exchangedwith the high temperature/high pressure coolant inflowed to the inside.

The expansion valve 47 is provided on the refrigerant line 41 betweenthe heater 45 and the heat exchanger 49. This expansion valve 47 mayexpand the coolant in the vehicle's heating mode and flow it into theheat exchanger 49.

The heat exchanger 49 is connected to the refrigerant line 41 to allowthe coolant to pass therethrough, and is respectively connected to thefirst and second coolant lines 11 and 21 to respectively pass throughthe first and second coolants circulating in the first and secondcooling apparatus 10 and 20.

Here, the heat exchanger 49 may condense or evaporate the refrigerantthrough heat exchange with the first and second coolants suppliedthrough the first and second coolant lines 11 and 21 according to thecooling mode or the heating mode of the vehicle. The heat exchanger 49may be a water-cooled heat exchanger in which the coolant flows.

That is, the heat exchanger 49 may evaporate the refrigerant when theexpansion valve 47 expands the refrigerant and condense the refrigerantwhen the expansion valve 47 flows in the refrigerant without expandingthe refrigerant.

Meanwhile, the heat exchanger 49 may recover thermal energy from thefirst and second coolants flowing through the first and second coolantlines 11 and 21 in the vehicle's heating mode, and increase thetemperature of the refrigerant by use of the recovered heat energy.

That is, the heat exchanger 49 may recover thermal energy from the firstcoolant of which the temperature is increased while circulating throughthe electrical component 15 without the passing through the firstradiator 12 along the first coolant line 11 and the branch line 18through operation of the valve 16 in the heating mode of the vehicle,and increase the temperature of the refrigerant by use of the recoveredheat energy.

Furthermore, if the heat source of the electrical component 15 isinsufficient in the heating mode at the beginning of the driving of thevehicle, the heat exchanger 49 may recover the thermal energy from thesecond coolant of which the temperature is increased by absorbing theheat of the external heat source while passing through the secondradiator 22 in the second cooling apparatus 20, and may increase thetemperature of the refrigerant by use of the thermal energy recoveredfrom the first and second coolants.

In other words, the heat exchanger 49 may recover thermal energy fromthe first and second coolants of which the temperature is increased byabsorbing the waste heat and heat from the external heat source of theelectrical component 15, and may simultaneously evaporate therefrigerant by use of the first and second coolants of which thetemperature is elevated, the temperature of the refrigerant may beefficiently increased.

The refrigerant of which the temperature rises in the heat exchanger 49may be supplied to the compressor 43.

On the other hand, the air conditioning apparatus 40 may further includeanother non-illustrated expansion valve and an evaporator providedinside the HVAC module and connected to the refrigerant line 41.

The other expansion valve receives and expands the refrigerant exhaustedfrom the heat exchanger 49 in the vehicle's cooling mode, and suppliesthe expanded refrigerant to the non-illustrated evaporator.

The evaporator cools the outside air while evaporating the expandedrefrigerant through heat exchange with the outside air. The cooledoutside air flows into the interior of the vehicle, cooling the interiorof the vehicle.

The control method of the heat pump system configured as described abovemay be used when heating the vehicle by selectively recovering thermalenergy generated from the electrical component 15 and the external heatsource when the vehicle is driven.

The control method of the heat pump system configured as described aboveto be used when heating the vehicle by selectively recovering thermalenergy generated from the electrical component 15 and the external heatsource when the vehicle is driven includes: a process A of heating thevehicle interior while the vehicle is running and operating the firstcooling apparatus 10; a process B of detecting the temperature of thefirst coolant circulated in the first cooling apparatus 10 and thetemperature of the second coolant in the second cooling apparatus 20 anddetermining whether a difference value of the first coolant temperatureand the second coolant temperature is higher than a predeterminedtemperature; and a process C of controlling an operation of the secondwater pump 24 by comparing the difference value of the first coolanttemperature and the second coolant temperature with the predeterminedtemperature through the process B and finishing the control.

First, in the process A, the controller 50 operates the heating mode ofthe vehicle according to the operation or setting of the user while thevehicle is driving (S1).

The controller 50 then operates the compressor 43 to circulate therefrigerant in the air conditioning apparatus 40 (S2).

Furthermore, the controller 50 controls the valve 16 to open the branchline 18 and to operate the first water pump 14 (S3).

That is, the valve 16 may connect the first coolant line 11 and thebranch line 18 connected to the electrical component 15, and may preventthe first coolant from inflowing to the first coolant line 11 connectedto the first radiator 12.

Thus, the first coolant may be supplied to the heat exchanger 49 alongthe branch line 18 and the first coolant line 11 that are open throughoperation of the first water pump 14 in the state that it is heatedwhile circulating through the electrical component 15 without passingthrough the first radiator 12.

Here, the first coolant is raised in temperature by heat exchange withthermal energy generated from the electrical component 14 while thevehicle is running.

Accordingly, in the heat exchanger 49, the thermal energy may berecovered from the first coolant inflowed through the first coolant line11 and having the increased temperature.

In the process B, the controller 50 detects the temperature of the firstand second coolants through the output signal output from the first andsecond coolant temperature sensors 17 and 27.

Accordingly, the controller 50 determines whether the difference valuebetween the first coolant temperature and the second coolant temperatureis higher than the predetermined temperature (S5).

Also, in the step (S5) of determining whether the difference valuebetween the first coolant temperature and the second coolant temperatureis higher than the predetermined temperature, if the condition issatisfied, the process C maintains the state in which the operation ofthe second water pump 24 is interrupted and the operation of the secondwater pump 24 is stopped (S6), and finishes the control.

That is, when the thermal energy recovered from the electrical component15 is sufficient during the initial driving of the vehicle, the heatingmode of the vehicle may be smoothly performed by use of the heat of thewaste heat source of the electrical component 15 without the operationof the second cooling apparatus 20.

In contrast, in the step (S5) of determining whether the differencevalue of the temperature of the first coolant and the temperature of thesecond coolant is higher than the predetermined temperature, if thecondition is not satisfied, the controller 50 operates the second waterpump 24 (S7).

Next, the controller 50 may open the cooling fan 13 mounted at the rearof the first radiator 12 or an active air flap 30 provided in thevehicle at the front of the second radiator 22 (S8), and may returned tothe process B.

That is, when the thermal energy recovered from the electrical component15 is insufficient during the initial driving of the vehicle, thecontroller 50 circulates the second coolant through operation of thesecond water pump 24 to absorb the heat of the external heat sourcethrough the second radiator 22.

Thus, the second coolant absorbs the heat of the external heat sourcethrough heat exchange with the outside air while passing through thesecond radiator 22 by the operation of the cooling fan 13, or the openactive air flap 30.

The heat of the external heat source absorbed in the second coolant maybe recovered through heat exchange with the refrigerant while passingthrough the heat exchanger 49, and the temperature of the refrigerantpassing through the heat exchanger 49 along with the heat of the wasteheat source of the electrical component 15 may be increased.

The refrigerant having the elevated temperature passes through theheater 45 in the state that it is compressed to a high temperature/highpressure while passing through the compressor 43, facilitating heatingof the vehicle interior.

That is, in the exemplary embodiment of the present invention, when thewaste heat source of the electrical component 15 is insufficient, theheat of the external heat source may be recovered together, the heatingmode of the vehicle may be smoothly and efficiently performed.

On the other hand, after performing the step (S8), the process isreturned to the process B and each above-described step is repeated.

Here, in the step (S5) of determining whether the difference value ofthe temperature of the first coolant and the temperature of the secondcoolant is higher than the predetermined temperature, if the conditionis satisfied, the controller 50 may stop the operation of the secondwater pump 24 and finish the control.

At the same time, the controller 50 may shut down the operation of thecooling fan 13 or close the open active air flap 30.

That is, while each above-described step is performed, the controller 50recovers the thermal energy generated from the electrical component 15if heating is required during the driving of the vehicle or at thebeginning of the driving, and recovers the heat of the external heatsource through operation of the second cooling apparatus 20 when thewaste heat source of the electrical component 15 is insufficient to beused together for heating, it is possible to minimize the operation ofan electric heater operated by power supplied from a non-illustratedbattery. At the same time, the usage amount of battery may be reduced.

As above-described, if the control method of the heat pump system forthe vehicle according to an exemplary embodiment of the presentinvention is applied, the thermal energy generated from the electricalcomponent 15 during the driving in the electric vehicle is recovered andthe heat of the external heat source is selectively recovered when theheat source is insufficient to be used in the heating mode of thevehicle, minimizing the usage amount of the electric heater.

Furthermore, the present invention prevents excessive power consumptionof the electric heater, increasing the overall travel distance of thevehicle through the efficient management of the battery, and it ispossible to reduce the battery charging cost by preventing unnecessarypower consumption.

Furthermore, the present invention may improve the overall marketabilityby increasing the travel distance of the vehicle and reducing thebattery charging cost.

For convenience in explanation and accurate definition in the appendedclaims, the terms “upper”, “lower”, “inner”, “outer”, “up”, “down”,“upwards”, “downwards”, “front”, “rear”, “back”, “inside”, “outside”,“inwardly”, “outwardly”, “internal”, “external”, “inner”, “outer”,“forwards”, and “backwards” are used to describe features of theexemplary embodiments with reference to the positions of such featuresas displayed in the figures. It will be further understood that the term“connect” or its derivatives refer both to direct and indirectconnection.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit thepresent invention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described toexplain certain principles of the present invention and their practicalapplication, to enable others skilled in the art to make and utilizevarious exemplary embodiments of the present invention, as well asvarious alternatives and modifications thereof. It is intended that thescope of the present invention be defined by the Claims appended heretoand their equivalents.

What is claimed is:
 1. A control method of a heat pump system for avehicle to be used for heating the vehicle by selectively recoveringthermal energy generated from an electrical component and an externalheat source when the vehicle is running, in the heat pump systemincluding: a first cooling apparatus including a first radiator, a firstwater pump, the electrical component, a valve, and a branch line, whichare connected by a first coolant line, wherein a first coolant iscirculated by the first water pump to the electrical component; a secondcooling apparatus including a second radiator and a second water pumpconnected by a second coolant line; and an air conditioning apparatusincluding a compressor, a heater, an expansion valve, and a heatexchanger which are connected by a refrigerant line circulated with arefrigerant, wherein the heat exchanger is connected to the first andsecond coolant lines respectively, and the heat pump system iscontrolled by a controller, the control method comprising: a process (A)of performing heating of a vehicle interior when the vehicle is runningand operating the first cooling apparatus; a process (B) of detecting atemperature of a first coolant circulated in the first cooling apparatusand a temperature of a second coolant in the second cooling apparatusand determining when a difference value of the first coolant temperatureand the second coolant temperature is higher than a predeterminedtemperature; and a process (C) of controlling operation of the secondwater pump and finishing the control by comparing the difference valueof the temperature of the first coolant and the temperature of thesecond coolant with the predetermined temperature through the process(B).
 2. The control method of the heat pump system for the vehicle ofclaim 1, wherein the process (A) includes: starting, by the controller,the heating of the vehicle according to an operation or setting of auser during driving of the vehicle; operating the compressor of the airconditioning apparatus by the controller; and controlling the valve bythe controller to open the branch line and to operate the first waterpump.
 3. The control method of the heat pump system for the vehicle ofclaim 2, wherein, when a heating mode of the vehicle is performed, in astate that the first coolant line is connected to the branch line andthe electrical component, the valve is configured to close the firstcoolant line connected to the first radiator by a control signal of thecontroller to stop an inflow of the coolant to the first radiator. 4.The control method of the heat pump system for the vehicle of claim 1,wherein the process (B) includes: detecting a temperature of the firstand second coolants by the controller through an output signal outputfrom the first and second coolant temperature sensors; and determiningwhen the difference value of the temperature of the first coolant andthe temperature of the second coolant is higher than the predeterminedtemperature.
 5. The control method of the heat pump system for thevehicle of claim 4, wherein the first coolant temperature sensor detectsthe temperature of the first coolant circulated in the first coolingapparatus, and wherein the second coolant temperature sensor detects thetemperature of the second coolant circulated in the second coolingapparatus.
 6. The control method of the heat pump system for the vehicleof claim 4, wherein when the difference of the first coolant temperatureand the second coolant temperature is determined to be higher than thepredetermined temperature, the process (C) includes maintaining a statein which an operation of the second water pump is interrupted or theoperation of the second water pump is stopped or finishing the control.7. The control method of the heat pump system for the vehicle of claim4, wherein when the difference of the first coolant temperature and thesecond coolant temperature is equal to or lower than the predeterminedtemperature, the process (C) includes operating the second water pump.8. The control method of the heat pump system for the vehicle of claim7, further including, in the process (C), after operating the secondwater pump, operating a cooling fan mounted at a rear of the firstradiator or opening an air flap mounted in the vehicle at a front of thesecond radiator, and returning the control method to the process (B). 9.The control method of the heat pump system for the vehicle of claim 1,wherein, in the heat exchanger, the thermal energy accumulates from thefirst and second coolants inflowing through the first and second coolantlines.
 10. A heat pump system for a vehicle to be used for heating thevehicle by selectively recovering thermal energy generated from anelectrical component and an external heat source when the vehicle isrunning, the heat pump system comprising: a first cooling apparatusincluding a first radiator, a first water pump, the electricalcomponent, a valve, and a branch line, which are connected by a firstcoolant line, wherein a first coolant is circulated by the first waterpump to the electrical component; a second cooling apparatus including asecond radiator and a second water pump connected by a second coolantline; an air conditioning apparatus including a compressor, a heater, anexpansion valve, and a heat exchanger which are connected by arefrigerant line circulated with a refrigerant, wherein the heatexchanger is connected to the first and second coolant linesrespectively; and a controller configured of controlling the heat pumpsystem.
 11. The heat pump system for the vehicle of claim 10, whereinthe controller is configured of: (A) a process of performing heating ofa vehicle interior when the vehicle is running and operating the firstcooling apparatus; (B) a process of detecting a temperature of a firstcoolant circulated in the first cooling apparatus and a temperature of asecond coolant in the second cooling apparatus and determining when adifference value of the first coolant temperature and the second coolanttemperature is higher than a predetermined temperature; and (C) aprocess of controlling operation of the second water pump and finishingthe control by comparing the difference value of the temperature of thefirst coolant and the temperature of the second coolant with thepredetermined temperature through the process (B).
 12. The heat pumpsystem for the vehicle of claim 11, wherein the process (A) includes:starting, by the controller, the heating of the vehicle according to anoperation or setting of a user during driving of the vehicle; operatingthe compressor of the air conditioning apparatus by the controller; andcontrolling the valve by the controller to open the branch line and tooperate the first water pump.
 13. The heat pump system for the vehicleof claim 12, wherein, when a heating mode of the vehicle is performed,in a state that the first coolant line is connected to the branch lineand the electrical component, the valve is configured to close the firstcoolant line connected to the first radiator by a control signal of thecontroller to stop an inflow of the coolant to the first radiator. 14.The heat pump system for the vehicle of claim 11, wherein the process(B) includes: detecting the temperatures of the first and secondcoolants by the controller through an output signal output from thefirst and second coolant temperature sensors; and determining when thedifference value of the temperature of the first coolant and thetemperature of the second coolant is higher than the predeterminedtemperature.
 15. The heat pump system for the vehicle of claim 14,wherein the first coolant temperature sensor detects the temperature ofthe first coolant circulated in the first cooling apparatus, and whereinthe second coolant temperature sensor detects the temperature of thesecond coolant circulated in the second cooling apparatus.
 16. The heatpump system for the vehicle of claim 14, wherein when the difference ofthe first coolant temperature and the second coolant temperature isdetermined to be higher than the predetermined temperature, the process(C) includes maintaining a state in which an operation of the secondwater pump is interrupted or the operation of the second water pump isstopped or finishing the control.
 17. The heat pump system for thevehicle of claim 14, wherein when the difference of the first coolanttemperature and the second coolant temperature is equal to or lower thanthe predetermined temperature, the process (C) includes operating thesecond water pump.
 18. The heat pump system for the vehicle of claim 17,further including, in the process (C), after operating the second waterpump, operating a cooling fan mounted at a rear of the first radiator oropening an air flap mounted in the vehicle at a front of the secondradiator, and returning to the process (B).
 19. The heat pump system forthe vehicle of claim 10, wherein, in the heat exchanger, the thermalenergy accumulates from the first and second coolants inflowing throughthe first and second coolant lines.